Paste and Gel Properties of Prime Corn and Wheat Starches With and Without Native Lipids'

Corn starch showed higher fresh paste consistency than wheat starch, and, after aging 24 hr, its gels were more firm at 6% solids or less. Between 7 and 30% solids, gels of wheat starch were more firm than those of corn starch. The lipids in wheat and corn starches were reduced 88-97% by boiling three times in four parts of a 3:1 (v/v) mixture of ethanol/water. Iodine-binding capacity of corn and wheat starches was highest after extraction with 75% n-propanol at 100IC compared to other solvents. Soxhlet extraction with methanol removed 93% lipid from corn starch, but only 78% from wheat starch as judged by iodine-binding capacity; hot 75% ethanol removed 97% lipid from wheat starch, but only 88% from corn starch. Amylograms of the low-lipid starches in 1% carboxymethylcellulose showed an initial, rapid increase in consistency as temperature rose 10° C beyond gelatinization. Then, consistency increased slowly and steadily up